Inertia tripod synchronization system

ABSTRACT

An inertia tripod member is adapted to be coupled to a rotating member of an archery bow. The inertia tripod member includes a central body portion offset from the rotating member. A synchronization leg extends out from the central body portion and is coupled to the rotating member for synchronizing rotation of the inertia tripod member with rotation of the rotating member. An inertia thrust leg extends out from the central body portion and is spaced apart from the synchronization leg for increasing catapulting forces and bow speed during each shot of the archery bow.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to and all the benefits of U.S. Provisional Application Ser. No. 60/644,691, filed Jan. 18, 2005 and entitled “Inertia Tripod Synchronization System.”

FIELD OF THE INVENTION

The invention relates to an archery bow. More particularly, this invention relates to an inertia tripod member coupled to a rotating member of an archery bow to increase catapulting forces and bow speed during each shot of an archery bow.

DESCRIPTION OF RELATED ART

In certain archery bows, such as compound bows and cross bows, inertial damping technology has been utilized within a cam and/or wheel through use of an inertial disc. In this so-called concentric-inline inertia technology, the inertial disc, which is a damping member, is incorporated within the cam or wheel so that the inertia disc is always concentric and in line with the cam or wheel. One problem with this concentric-inline inertia technology is that placement of the inertial disc is restricted to the surface of the cam or wheel due to the positioning of other cam or wheel features. As a result, optimization of the mass-moment of inertia of the cam or wheel is also restricted.

Another limiting factor in the concentric-inline inertia technology is the placement of the inertial disc within a main body of the cam or the wheel. Such placement of the inertial disc limits the efficiency of centripetal forces or catapulting forces. The centripetal forces in the concentric-inline inertia technology act in-line and concentric with the cam or wheel, which reduces the centripetal force efficiency even further. The reason for such reduced centripetal force efficiency is the fact that the string and cable forces acting on the cam or wheel once the archery bow has been shot counter-reacts any centripetal force generated by the inertial disc. The string or cables prevent the inertia disc from catapulting to its maximum efficiency.

SUMMARY OF THE INVENTION

According to one aspect of the invention, an inertia tripod member is adapted to be coupled to a rotating member of an archery bow. The inertia tripod member includes a central body portion spaced apart and offset from the rotating member. A synchronization leg extends out from the central body portion and is coupled to the rotating member for synchronizing rotation of the inertia tripod member with rotation of the rotating member. An inertia thrust leg extends out from the central body portion and is spaced apart from the synchronization leg for increasing catapulting forces and bow speed during each shot of the archery bow.

According to another aspect of the invention, an inertia tripod member is provided for an archery bow having a rotating member. The inertia tripod member includes a central body portion adapted to be coupled to the rotating member. An inertia thrust leg extends out from the central body portion. The inertia thrust leg includes an inertial disc weight fixedly secured thereto for increasing catapulting forces and bow speed during each shot of the archery bow.

According to yet another aspect of the invention, an inertia tripod member is adapted to be coupled to a rotating member of an archery bow. The inertia tripod member includes a central body portion. A synchronization leg extends out from the central body portion and is coupled to the rotating member for synchronizing rotation of the inertia tripod member with rotation of the rotating member. A draw length adjustable leg extends out from the central body portion and is spaced apart from the synchronization leg for limiting rotation of the rotating member at full draw of the archery bow. An inertia thrust leg extends out from the central body portion and is spaced apart from the synchronization and draw length adjustable legs for increasing catapulting forces and bow speed during each shot of the archery bow.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a perspective view of an archery bow including an inertia tripod member according to the invention coupled to a cam;

FIG. 2 is a perspective view of the inertia tripod member coupled to the cam at one end of a limb;

FIG. 3 is an end view of the inertia tripod member coupled to the cam at one end of the limb;

FIG. 4 is a lower, perspective view of the inertia tripod member;

FIG. 5 is an upper, perspective view of the inertia tripod member;

FIG. 6 is a perspective view of one of the limbs and an inertia tripod member, including a damping arm pad, coupled to the cam; and

FIG. 7 is a perspective view of the inertia tripod member having the damping arm pad.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, an archery bow, generally shown at 10, includes a riser 12 extending between opposing ends 14, 16. Although a compound bow is shown in FIG. 1, it is contemplated that the following description is equally applicable to other bows including, but not limited to, mechanical bows and cross bows. The archery bow 10 includes first 18 and second 20 limbs extending out from the respective ends 14, 16 of the riser 12. Each of the first 18 and second 20 limbs includes a first end 22 proximate to one end 14, 16 of the riser 12. A pair of limb pockets 24, 26 pivotally attaches the first 18 and second 20 limbs to the respective ends 14, 16 of the riser 12.

A rotating member 28, 30 is rotatably coupled to an opposing second end 32 of each of the first 18 and second 20 limbs. Preferably, the rotating members are a wheel 28 and a cam 30. A harness or cable system 34 and a bowstring 36 are wound around and between each of the wheel 28 and cam 30 and pulled in tension by the first 18 and second 20 limbs. A cable guard slide 37 having rollers 39 extends between the riser 12 and the harness or cable system 34.

Referring to FIGS. 2 through 5, an inertia tripod member, generally indicated at 38, is adapted to be coupled to the cam 30. It should be appreciated that although the inertia tripod member 38 is shown and described as being coupled to the cam 30, the inertia tripod member 38 may also be coupled to the wheel 28. The inertia tripod member 38 includes a central body portion 40. The central body portion 40 includes a bearing housing 42 for receiving a ball bearing 44. The ball bearing 44 defines an aperture 46 extending through the central body portion 40. A fastener 48 extends through the aperture 46 to rotatably mount the inertia tripod member 38 to one of the limbs 20.

In an exemplary embodiment, the inertia tripod member 38 is mounted about the fastener 48 outboard of the limb 20, as shown in FIGS. 1 through 3. It is, however, appreciated that the inertia tripod member 38 may be mounted about the fastener 48 inboard of the limb 20, that is, between the limb 20 and the cam 30. Regardless of the mounting position of the inertia tripod member 38, the inertia tripod member 38 is offset from the cam 30. More specifically, the inertia tripod member 38 is not housed within any part of the cam 30 including a cavity, hollow, pocket or any other housing formed therein or therealong. As a result, the inertia tripod member 38 optimizes centripetal or catapulting forces generated by the cam 30 during each shot of the archery bow 10, which in turn increases bow speed and shot accuracy.

The inertia tripod member 38 may be utilized at each rotating member 30 of a compound bow, a one cam bow, a cam & half bow, or a cross bow.

The inertia tripod member 38 also includes a synchronization leg 50, an inertia thrust leg 52, and a draw leg 54 each extending out from the central body portion 40 and spaced apart from one another. The synchronization leg 50 includes a fastener 56 at a distal end 58 for coupling to the cam 30. The synchronization leg 50 may, however, be coupled to the cam 30 in any of numerous ways including, but not limited to, via a bolt, dowel, keyed shaft, and bonding agent. As a result, rotation of the inertia tripod member 38 is synchronized with rotation of the cam 30 but occurs offset from the cam 30.

In a preferred embodiment, the synchronization leg 50 includes a damping member 60 at the distal end 56. The damping member 60 reduces vibration at the distal end 58 of the synchronization leg 50. It is, however, contemplated that any of numerous damping materials may be placed at the distal end 58 of the synchronization leg 50.

The inertia thrust leg 52 extending out from the central body portion 40 terminates at a distal end 62. The inertia thrust leg 52 is preferably J-shaped, which allows the inertia tripod member 38 to optimize catapulting forces during each shot of the archery bow 10. It is, however, appreciated that the geometry of the inertia thrust leg 52 may be adjusted to further optimize catapulting forces and bow speed.

An opening 64 is formed at the distal end 62. An inertial disc weight 66 is received within the opening 64. The weight of the inertial disc weight 66 may vary but it is appreciated that the greater the weight, the greater the catapulting forces and bow speed. The inertial disc weight 66 preferably has a density greater than 0.1 lb/cu.in. The inertial disc weight 66 is preferably formed from tungsten carbide. It is, however, appreciated that any of numerous materials or similar density may be utilized for the inertia disc weight 66. The inertial disc weight 66 can be heavier or lighter in weight than the synchronization leg 50.

Since the inertia tripod member 38 is offset from the cam 30 and synchronized therewith, the size and location of the inertial disc weight 66 is not limited by cam components. The inertial disc weight 66 may be placed at various locations along the inertia tripod member 38 and secured thereto in any of various methods including, but not limited to, gluing, bolting, bonding, doweling, and press fitting. The inertial disc weight 66 may also be secured to the cable guard slide 37 or the rollers 39 thereof.

A radius moment R is defined as the distance between the center of the inertial disc weight 66 and the center of rotation of the inertia tripod member 38. It is recognized that the radius moment R may vary. The greater the radius moment R, the greater the catapulting forces and bow speed.

The draw length adjustable leg 54 extending out from the central body portion 40. The draw length adjustable leg 54 includes a plurality of spaced apart threaded holes 68 extending therethrough. A draw stop rubber pad 70 is threadedly received within one of the plurality of spaced apart threaded holes 68. The draw stop rubber pad 70 pads against the limb 20 at full draw and prevents a user from over-drawing the archery bow 10. The draw stop rubber pad 70 may be threaded into any of the plurality of spaced apart threaded holes 68 in order to adjust the draw length of the archery bow 10.

Referring to FIGS. 6 and 7, the inertia tripod member 38 in another embodiment includes a damping arm pad 76 fixedly secured to synchronization leg 50 for damping against the limb 20 to reduce the “feel” of the thrust or inertia. Thus, the damping arm pad 76 rotates with the cam 30. The damping arm pad 76 may be formed from any of numerous damping materials including, but not limited to, elastomeric material and foam. It is contemplated that although the damping arm pad 76 has been shown and described as being fixedly secured to the synchronization leg 50, the damping arm pad 76 may be fixedly secured to the limb 20 so that the inertia tripod member 38 rotates relative to the damping arm pad 76.

The invention has been described in an illustrative manner. It is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the invention may be practiced other than as specifically described. 

1. An inertia tripod member adapted to be coupled to a rotating member of an archery bow, said inertia tripod member comprising: a central body portion offset from the rotating member; a synchronization leg extending out from said central body portion and coupled to the rotating member for synchronizing rotation of said inertia tripod member with rotation of the rotating member; and an inertia thrust leg extending out from said central body portion and spaced apart from said synchronization leg for increasing catapulting forces and bow speed during each shot of the archery bow.
 2. An inertia tripod member as set forth in claim 1 wherein said synchronization leg includes a damping member for dampening vibration and noise during each shot of the archery bow.
 3. An inertia tripod member as set forth in claim 2 wherein said central body portion includes a bearing housing.
 4. An inertia tripod member as set forth in claim 3 including a ball bearing received within said bearing housing.
 5. An inertia tripod member as set forth in claim 1 wherein said inertia thrust leg includes an inertial disc weight fixedly secured thereto.
 6. An inertia tripod member as set forth in claim 1 wherein said inertia thrust leg is generally J-shaped.
 7. An inertia tripod member as set forth in claim 1 including a damping arm pad fixedly secured to said cam synchronization leg for dampening vibration at full draw of the archery bow.
 8. An inertia tripod member as set forth in claim 7 wherein said damping arm pad is formed from an elastomeric material.
 9. An inertia tripod member for an archery bow having a rotating member, said inertia tripod member comprising: a central body portion adapted to be coupled to the rotating member; and an inertia thrust leg extending out from said central body portion, said inertia thrust leg having an inertial disc weight fixedly secured thereto for increasing catapulting forces and bow speed during each shot of the archery bow.
 10. An inertia tripod member as set forth in claim 9 wherein said inertia thrust leg has a predetermined geometry configured to increase catapulting forces and bow speed.
 11. An inertia tripod member as set forth in claim 10 wherein said inertia thrust leg is generally J-shaped.
 12. An inertia tripod member as set forth in claim 9 including a radius moment defined by a distance between a center of said inertial disc weight and a center of said central body portion.
 13. An inertia tripod member adapted to be coupled to a rotating member of an archery bow, said inertia tripod member comprising: a central body portion; a synchronization leg extending out from said central body portion and coupled to the rotating member for synchronizing rotation of said inertia tripod member with rotation of the rotating member; a draw length adjustable leg extending out from said central body portion and spaced apart from said synchronization leg for limiting rotation of the rotating member at full draw of the archery bow; and an inertia thrust leg extending out from said central body portion and spaced apart from said synchronization and draw length adjustable legs for increasing catapulting forces and bow speed during each shot of the bow.
 14. An inertia tripod member as set forth in claim 13 wherein said draw length adjustable leg includes a plurality of spaced apart threaded holes.
 15. An inertia tripod member as set forth in claim 14 including a draw stop rubber pad selectively received within one of said plurality of spaced apart threaded holes for defining full draw of the archery bow.
 16. An inertia tripod member as set forth in claim 13 wherein said inertia thrust leg includes an inertial disc weight fixedly secured thereto.
 17. An inertia tripod member as set forth in claim 13 wherein said inertia thrust leg is generally J-shaped.
 18. An inertia tripod member as set forth in claim 13 including a damping arm pad fixedly secured to said cam synchronization leg for dampening vibration at full draw of the archery bow.
 19. An inertia tripod member as set forth in claim 18 wherein said damping arm pad is formed from an elastomeric material. 